| Paper | Title | Page |
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| MOPC108 | AGS Polarized Proton Operation in Run 8 | 316 |
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| A dual partial snake scheme has been used for AGS polarized proton operation for several years. It has provided polarized proton beams with 1.5*1011 protons per bunch and 65% polarization for the RHIC spin program. There is still residual polarization loss due to both snake resonances and horizontal resonances. Several schemes were tested in the AGS to mitigate the loss. This paper presents the experiment results and analysis. | ||
| MOPC117 | Hybrid Snake Spin Resonance in RHIC | 337 |
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| Simulations reveal a potential polarization loss during low beta squeeze. This depolarization appears to be driven by a spin tune modulation caused by spin precession through the strong low beta quads due to the vertical fields. The modulation of the spin tune introduces an additional snake resonance condition at νs0 ± n νx - νz l = integer which while the same numerology as the well known sextupole resonance, can operate in the absence of sextupole elements. | ||
| TUPP097 | New Formalism in the Spin Tracking Code Spink | 1756 |
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The code Spink*, in use for more than 10 years to track polarized hadrons in a synchrotron, was overhauled with the introduction of a new system of coordinates based on a generalized Frenet-Serret system in all dimensions in space, which allows a better treatment of the curvature of the reference orbit. Two more improvements are (a) treatment of tensor polarization for particles like polarized deuterons, and (b) inclusion of space charge and beam-beam effects, so the code can be used to track spin in synchrotrons with high luminosity like new generation colliders.
*A. U. Luccio. Proc. Adriatico Research Conf. on Trends in Colliders |
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| THPC023 | Optimization of the AGS Superconducting Helical Partial Snake Strength | 3026 |
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| Two helical partial snakes, one is superconducting (called cold snake) and one is normal conducting (called warm snake), have preserved the polarization of proton beam up to 65% at the AGS extraction energy with the inject 82% polarization. In order to overcome the spin resonances, stronger partial snake is required. However, the stronger partial snake, the more titled stable spin direction that results in stronger horizontal intrinsic resonance. The balance between raising the spin tune gap generated by the snakes and reducing the titled stable spin direction has to be considered to maintain the polarization. Because the magnetic field of the warm snake is constant, only the cold snake with a maximum 3T magnetic field can be varied to find out the optimized snake strength. The paper presents the simulation results from the spin tracking with different cold snake magnetic fields. Some experimental data are also analyzed. | ||
| WEPP019 | RHIC Polarized Proton Performance in Run-8 | 2566 |
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| During Run-8, the Relativistic Heavy Ion Collider (RHIC) provided collisions of spin-polarized proton beams at two interaction regions. Helical spin rotators at these two interaction regions were used to control the spin orientation of both beams at the collision points. Physics data were taken with different orientations of the beam polarization. We present recent developments and improvements as well as the luminosity and polarization performance achieved during Run-8. | ||
| THPC060 | Spin Flip of Deuterons in COSY - Spink Tracking | 3122 |
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The spin tracking code Spink, as recently overhauled*, has been used to study the deuteron spin resonances and spin flipping induced by a RF dipole and a RF solenoid. The modifications of the code followed extended discussions on the formalism used to model spin evolution in a synchrotron. The simulation shows a good agreement with published results of the measurements**.
*A. U. Luccio et al. See another contribution to this Conference. |